#include <OneWire.h>

// Enable following define for extra debug info
//#define DBG_PRINTS

// DS18S20 Temperature chip i/o
OneWire ds(10);  // on pin 10

/*
Device address:
  DS18B20: 0x28
  DS18S20: 0x10
*/

void setup(void) {
  // initialize inputs/outputs
  // start serial port
  Serial.begin(57600);
}

void loop(void) {
  byte i;
  byte present = 0;
  byte data[12];
  byte addr[8];

  if ( !ds.search(addr)) {
#ifdef DBG_PRINTS    
      Serial.print("No more addresses.\n");
#endif
      ds.reset_search();
      return;
  }
  
#ifdef DBG_PRINTS   
  Serial.print("R=");
  for( i = 0; i < 8; i++) {
    Serial.print(addr[i], HEX);
    Serial.print(" ");
  }
#endif

  if ( OneWire::crc8( addr, 7) != addr[7]) {
#ifdef DBG_PRINTS      
      Serial.print("CRC is not valid!\n");
#endif
      return;
  }

  if ( addr[0] != 0x28) {
#ifdef DBG_PRINTS      
      Serial.print("Device is not a DS18S20 family device.\n");
#endif
      delay(1000);
      return;
  }
  
  ds.reset();
  ds.select(addr);
  ds.write(0x44,1);         // start conversion, with parasite power on at the end

  delay(1000);     // maybe 750ms is enough, maybe not
  // we might do a ds.depower() here, but the reset will take care of it.

  present = ds.reset();
  ds.select(addr);    
  ds.write(0xBE);         // Read Scratchpad

#ifdef DBG_PRINTS  
  Serial.print("P=");
  Serial.print(present,HEX);
  Serial.print(" ");
#endif
  for ( i = 0; i < 9; i++) {           // we need 9 bytes
    data[i] = ds.read();
#ifdef DBG_PRINTS  
    Serial.print(data[i], HEX);
    Serial.print(" ");
#endif
  }
#ifdef DBG_PRINTS  
  Serial.print(" CRC=");
  Serial.print( OneWire::crc8( data, 8), HEX);
  Serial.println();
#endif
  
  Serial.print("Temp = ");
  convert_hex_to_temp_B_series(data);
}


void convert_hex_to_temp_B_series(byte data[12]){
int HighByte, LowByte, TReading, SignBit, Tc_100, Whole, Fract;

 LowByte = data[0];
  HighByte = data[1];
  TReading = (HighByte << 8) + LowByte;
  SignBit = TReading & 0x8000;  // test most sig bit
  if (SignBit) // negative
  {
    TReading = (TReading ^ 0xffff) + 1; // 2's comp
  }
  Tc_100 = (6 * TReading) + TReading / 4;    // multiply by (100 * 0.0625) or 6.25

  Whole = Tc_100 / 100;  // separate off the whole and fractional portions
  Fract = Tc_100 % 100;


  if (SignBit) // If its negative
  {
     Serial.print("-");
  }
  Serial.print(Whole);
  Serial.print(".");
  if (Fract < 10)
  {
     Serial.print("0");
  }
  Serial.print(Fract);

  Serial.print("\n");
}

void convert_hex_to_temp_S_series(byte data[12]){
int HighByte, LowByte, TReading, SignBit, Tc_10, Whole, Fract;


 LowByte = data[0];
  HighByte = data[1];
  TReading = (HighByte << 8) + LowByte;
  SignBit = TReading & 0x8000;  // test most sig bit
  if (SignBit) // negative
  {
    TReading = (TReading ^ 0xffff) + 1; // 2's comp
  }
  Tc_10 = (5 * TReading);    // multiply by 5

  Whole = Tc_10 / 10;  // separate off the whole and fractional portions
  Fract = Tc_10 % 10;


  if (SignBit) // If its negative
  {
     Serial.print("-");
  }
  Serial.print(Whole);
  Serial.print(".");
  if (Fract < 10)
  {
     Serial.print("0");
  }
  Serial.print(Fract);

  Serial.print("\n");
}

